Katz said he instructed the heads of his ministry to launch an investigation into how the contamination occurred. He said clearing the stranded flights was an immediate priority and that he would ensure that the necessary emergency fuel reserves are supplied in order to achieve that goal.

To aid in the resumption of flights from Ben Gurion, Paz, Israel's largest gas company, agreed to loan tens of fuel trucks to the airport.

Israel's airport authority estimated flights will resume at Ben Gurion at midnight. Planes will be given enough fuel to safely reach Larnaca Airport in Cyprus for fueling before proceeding to their final destinations.

El Al said it canceled some 20 flights Thursday and provided full refunds to passengers.

Israel Airports Authority spokesman Adar Avisar said Thursday the cause of the contamination remains unknown, but that it was spotted before any planes could take off with contaminated fuel.

Only planes with enough clean fuel to make it to their next destination were allowed to depart the airport

"There are no planes in the air that have received an order to land," Avisar said.

Following the discovery of the contaminated fuel, National Infrastructure Minister Uzi Landau (Israel Beitenu) issued a statement calling for the immediate establishment of a commission of inquiry.

Flights scheduled to land in and depart from Ben-Gurion on Thursday were redirected to Cyprus and Jordan for refueling during the day.